Stkainiitci-saws ikt sawmills



i u l TEDsTATEs PATENT oEErcE.

EDMUND BOOTH, 0E PHILADELPHIA, PENNSYLVANIA.

sTEAiNINe saws 1N sAwMILLs. y

` Specification of Letters Patent No. 8,954, datedMay 18, 14852.

. To all whom it may concern:

Be it known that I, EDMUNnBooTH, of the city and county of Philadelphiaand State of` Pennsylvania, have invented certain new and usefulImprovements in the Mode of Hanging Reciprocating Saws; and I `do herebydeclare that the following is a full, clear, and exact description ofthe same, reference being had tothe accompanying drawings, forming partof this specification, in which- Figure l, is a front elevation of a sawmill having my improvement attached. Fig. 2, is a vertical longitudinalsection showing the manner in which the lever is connected to thespring, and the guide rod. Fig. 3, is a detached and broken view,showing the frame in sect-ion and the working parts in elevation.

\ Similar letters of reference indicate corresponding parts in each ofthe several figures.

'Ihe nature of my invention consists in the `employment of a lever,passing through and working freely in, and up and down, an oblong slotcut in a vertical post secured to the top and nearly in the, center ofthe saw mill. This lever is attached atone end near its fulcrum, to arod or link which connects it to a spring secured to the top of the sawmill, and the other endis inserted into the upper guide rod of the sawand works in a slot in the same. The object effected by this lever is ofgreat importance, viz:` that of equalizing the strain or tension on thesaw when it is at highest or lowest point and thereby preventing the sawfrom kinking or bending as it is ascending, as is common for it to do,when the spring is attached directly to the guide rod of the saw,forwhen the saw is attached directly to the spring, the strain on it isgreatest when it is at its lowest point, and therefore it will be seen,

that when the saw is drawn upward it is liable to kink or buckle, andthereby cause considerable loss of time and labor in reset ting it,whereas by hanging or connecting the saw to the lever and spring in theman ner hereinafter described this diiculty is avoided, as the strain onthe saw is always equal no matter whether it be at its highest or lowestpointor up or down.

To enable others skilledvin the art to make and use my invention I willproceed to describe more fully its construction and operation.

A, A, represents theiframe of a saw mill and B, B, are the posts orcolumns supporting the same.

C, C, indicate' two posts, that lettered C, being securedto the top andnearly in the center of the `frame A, and the other lettered C', beingsecured in a line with the one .lettered C, to the bottom of the saidframe.

Between these posts there is a space left which is occupied by the saw.To the upper post C, boxes D, for the upper guide rods E, of the saw, tomove up and down in, are secured. There are also similar boxes D',secured to the lower post C, for the lower guide rod E', to move in. i

In the upper plate F, attached to the upper guides and throughthe upperpost C,

a vertical oblong mortise Gr, is cut. Through this mortise or slot,alever I-I, passes (as represented in Figs. 2 and 3 of the draw ings),and is secured at Ione end by means of a fulcrum pin a, to a smallstandard I, attached to the post C. The other end of this lever isinserted in the upperrguide rod E, of the saw J, in the mannerrepresented. The lever II, works up and down the slot G, and turnsfreely on its fulcrum a, and also works in the slot s, in the guide rodE.

L, represents a connecting link or rod, which moves and works in a slotcut in a brace ofthe frame and which connects the lever to the springM,;sccured to the top of the frame'in the manner shown in Fig. 2 of thedrawing or in any other suitable way. This link it will be seen byreferring to the drawing is connected to the lever or that part of thesame, lettered b, near its fulcrum a. By thus connecting the link of thespring near the fulcrum a, of the lever II, it will be seen that thelever II, (when the saw is in motion,) has, near its fulcrum, anoscillating motion and also that when the saw is drawn downward, thepart lettered b, to which the link L, connecting the lever to the springis attached, is thrown nearer to the fulcrum a, and farther from theweight and consequently more leverage is obtained to pull the springdownward, and when the saw is ascending the part of the lever letteredb, is thrown farther from the center or fulcrum a, and the end l, of thelever H, works freely in the slot s, as will be seen in Fig. 3, thuscausing the strain or tension on the saw either when up or down to beequal, or rather as the saw reaches its highest point the part of thelever lettered Z,

cause the rod to rise and hold the saw` always tight, and when the sawis at its lowest point the great strain` of the spring is taken awaypartially and an equal or the same amount of tension given to the saw atthat point as when at its highest point.

The saw is connected at one end' to the upper guide rod D, which isconnected to the lever H, and the other end passes through the slot e,through the top of the table N, and is also vconnected to the lowerguide rod D, secured to the post C, which is secured to the connectingrod O, of the crank 1P, which gives motion to the saw, through the iiywheel Q, and pulleys R, R, which are oper-- ated upon by any suitablepower.

Operation of the Zeven-When 'the saw' has made a half stroke downwardthe end Z, of the lever H, will move farther from the fulcrum a andoccupy the position indicated by a dotted line and star, inthe slot s,and; when it has made its full stroke down the lever will assume theposition shown in full force -or .thrust of which on the lever Causesthe end Z, of the lever to force the guide rod E, upward; and therebykeep the saw tight and also prevent i-t from kinking or :bending when itcommences `to rise :or fall.

The dotted arc of a circle, shown in red lines in Figs. 2 and 3,indicates the direction in which the part lettered Z2., moves.

I intend applying this improvement to every kind of saw to which it maybe ap` plicable, and therefore I do not intend to around, and allowingof logs being cross cut as well as slit, and another advantage is alsogained, as the sweep or stroke of the saw may be of any desired length,without any liability of its kinking or bending, this difficulty beingprevented by the equal distribution of strain on the saw both at thecommencement of its rising and falling.

Having thus fully described lthe natu-re and operation of my invention Iwill now state what I claim as new and 4desire to secure by LettersPatent.

' I claim- The employment of the lever H b Z, yor its equivalent, theVspring M, connectedl to the lever H, by a rod or link L, which issecured or attached to the lever near its fulc-rum a; both operatingtogether and in combination with a reciprocating saw, connected to the-lever H, and the whole being constructed and arranged and operatingsubstantially as herein described.

E. BOOTH.

Witnesses GEO. S. WiLLrrs,

JAS, S'roK-Es.

